The Freshwater Project - Rotomairewhenua

Rotomairewhenua (or Blue Lake) is a small lake in Nelson Lakes National Park, in the northern reaches of New Zealand's Southern Alps. The lake has the clearest natural body of fresh water yet reported. A 2011 study found its visibility ranged from 70 to 80 metres (230 to 260 ft), clearer than the 63 metres (207 ft) measured for Te Waikoropupu Springs, a previous record holder. For comparison, laboratory measurements show distilled water has a visibility of approximately 80 metres (260 ft). Scientists attribute the lake water's clarity to its passage underground from Lake Constance, which filters out nearly all the particles suspended in the water. Its clarity reveals water's natural blue-violet colour. This research was funded by NIWA, and supported by the Department of Conservation. NIWA is currently planning future surveys with DOC approval to more thoroughly investigate the biodiversity of Blue Lake, the limnology of Lake Constance and the connections between the two.
Blue Lake lies within the rohe (tribal area) of Ngati Apa ki te Ra To. As part of the iwi's 2010 treaty settlement, the lake passed into tribal ownership and was then given back to the Crown. The lake was traditionally used in ceremonies to cleanse the bones and release the spirits of the dead, so they could begin their journey to Hawaiki, and the iwi regard its waters as tapu (sacred). Blue Lake was used only for males; Lake Constance was used for females. Its Maori name Rotomairewhenua means "the lake of peaceful lands".

Freshwater Ecoregion of the World : #811 New Zealand

Major Habitat Type: temperate coastal rivers


U21-001	U21-002	U21-003	U21-004
U21-006	U21-007	U21-009	U21-010
U21-011	U21-012	U21-014	U21-015
U21-017	U21-018	U21-019	U21-020




U21-021	U21-022	U21-024	U21-025
U21-026	U21-027	U21-028	U21-029
U21-030	U21-031	U21-032	U21-033
U21-035	U21-038	U21-039	U21-040
U21-042	U21-043	U21-044	U21-045
U21-046	U21-048	U21-049	U21-056

Aerials and Landscapes


U21-502	U21-503	U21-504	U21-506 Lake Constance
U21-507	U21-508	U21-509	U21-510
U21-512	U21-513	U21-514	U21-515
U21-526	U21-527	U21-528	U21-529

Aerials : On the way to Rotomairewhenua


U21-518	R-155 Michel Roggo	U21-519 Lake Rotoroa	U21-520
U21-522	U21-523	U21-530	U21-531


The clearest freshwater ever reported – Rotomairewhenua, New Zealand








Rotomairewhenua (or Blue Lake) is a small lake in Nelson Lakes National Park, in the northern reaches of New Zealand's Southern Alps. The lake has the clearest natural body of fresh water yet reported. A 2011 study found its visibility ranged from 70 to 80 metres (230 to 260 ft), clearer than the 63 metres (207 ft) measured for Te Waikoropupu Springs, a previous record holder. For comparison, laboratory measurements show distilled water has a visibility of approximately 80 metres (260 ft). Scientists attribute the lake water's clarity to its passage underground from Lake Constance, which filters out nearly all the particles suspended in the water. Its clarity reveals water's natural blue-violet colour. This research was funded by NIWA, and supported by the Department of Conservation. NIWA is currently planning future surveys with DOC approval to more thoroughly investigate the biodiversity of Blue Lake, the limnology of Lake Constance and the connections between the two. Blue Lake lies within the rohe (tribal area) of Ngati Apa ki te Ra To. As part of the iwi's 2010 treaty settlement, the lake passed into tribal ownership and was then given back to the Crown. The lake was traditionally used in ceremonies to cleanse the bones and release the spirits of the dead, so they could begin their journey to Hawaiki, and the iwi regard its waters as tapu (sacred). Blue Lake was used only for males; Lake Constance was used for females. Its Maori name Rotomairewhenua means "the lake of peaceful lands". Freshwater Ecoregion of the World : #811 New Zealand Major Habitat Type: temperate coastal rivers


Produced in 2013. Red dots indicate personal favorites.

Underwater



Website Michel Roggo	Copyrights of all images, movies and other contents 2021 © Michel Roggo	The Freshwater Project Website